Arnold's seminar December 5th, 2000 Klaus Mohnke's proof of Arnold's chord conjecture Yuri Chekanov A contact form gives rise to the Reeb vector field, which is the contact vector field defined by contact Hamiltonian 1. A chord is a piece of Reeb trajectory connecting two points on a Legendrian submanifold. (A version of) the famous Arnold's chord conjecture claims that for each contact form defining the standard contact structure on the odd-dimensional sphere and each closed Legendrian submanifold, there exists a chord with ends on the submanifold. This conjecture, with generalizations to certain other contact manifold, has been recently proved by Klaus Mohnke. His proof will be presented in the talk.